How Marriage Makes For Mirror Images

NEW YORK — The belief that married couples begin to look alike may not be just an old wives' -- or old husbands' -- tale. Researchers are finding evidence that supports the idea.

A study by Robert Zajonc, a psychologist at the University of Michigan, shows that couples who looked nothing alike when married 25 years ago have come to resemble each other, although the resemblance may be subtle. And the more blissful the union, the greater the facial resemblance.

In his study, people were presented with a random array of photographs of faces, with the backgrounds blacked out, and were instructed to match the men with the women who most closely resembled them. Two dozen of the photographs were of couples when first married; another two dozen were of the same couples 25 years later, most taken around the time of their silver wedding anniversary.

All the couples in the photographs were white, lived in Michigan or Wisconsin and were between 50 and 60 years old at the time of the second picture.

The young couples showed only a chance similarity to each other, the study found, while the judges found a definite resemblance between the couples who had been married 25 years. Although the resemblances were not dramatic -- some seemed to involve subtle shifts in facial wrinkles and other facial contours, for instance -- they were marked enough that the judges were able to match husbands and wives far more often when the couples were older than when they were younger. And the resemblances were greater in some couples than in others, the study found.

Zajonc's explanation for this phenomenon: a kind of connubial copycatting. He says that people, often unconsciously, mimic the facial expressions of their spouses in a silent empathy. Over the years, sharing the same expressions shapes the face similarly.

Evidence for mimicry of expressions has come from research by Olaf Dimberg, a psychologist in Sweden, who measured the tension levels in the facial muscles of volunteers while they were shown photographs of various facial expressions. When the volunteers saw an angry face, for instance, their facial muscles mimicked the anger, often to a degree that was invisible but was measurable by electronic devices.

Zajonc suggested that shared facial expressions bring on identical emotions because facial muscles play a role in regulating blood flow to the brain. ''You both smile because you feel good and feel good because you smile,'' Zajonc said.

''Facial mimicry allows a truer empathy because it triggers the same inner state,'' Zajonc said. ''Couples can understand each other much better when this happens.''

One sign that such empathy has been going on, in Zajonc's view, is that people's fixed facial features begin to resemble those of their spouses as a result of sharing the same expressions so often. In support, he points to the finding in his study that those couples who were found to resemble each other most greatly after 25 years were also those who reported

the happiest marriages.

Not everyone empathizes with Zajonc. Although some experts agree that shared emotions could gradually sculpture the faces of a couple to become more similar, they do not agree with Zajonc's explanation.

''There is no question that we unwittingly use our facial muscles in the same way as the person we are looking at,'' said Paul Ekman, a psychologist at the University of California Medical School in San Francisco.

''Common life experiences over years and years can alter facial musculature and wrinkle patterns, leading to an increased resemblance, but there is no reason to believe that it has anything to do with blood flow to the brain,'' said Ekman, who is an expert on the muscles involved in emotional expression. His research has identified the configurations of the more than 100 facial muscles that compose each emotional expression.

Like other muscles of the body, facial muscles

grow or atrophy according to the amount of use; facial muscle activity, in turn, stimulates growth in facial bones. People who maintain a particular emotional stance toward life -- such as fear, disdain or joy -- may tend to hold the facial muscles involved in those feelings slightly tensed in a readiness to respond, Ekman contends. Over several decades, that tension can come to give the face a distinctive cast by altering wrinkle patterns, changing the relative size of different muscles and even bones, and so altering the contours of the face.

Another naysayer is Dr. Louis D'Alecy, professor of physiology and surgery at the University of Michigan. ''While facial blood flow can affect the temperature of blood going to the brain, it is hard to say how that would affect brain chemistry,'' he said.

Despite the debate over the link between facial expression and brain chemistry, some researchers agree with Zajonc's basic finding about the resemblance in spouses' faces. And none of them has proposed testing that other old wives' -- or husbands' -- tale that people likewise begin to resemble their pets.